According to a report in The Times this weekend, the number of crashes reported to police fell by 13%, or 1,643 a month, after licensing laws were reformed in 2005, according to the first such analysis of official data.
The decline has been felt most sharply among drivers aged between 18 and 25 and has been most marked on Friday and Saturday nights. Accidents involving young drivers at those times have fallen by 33%.
Economists at Lancaster University Management School said that, among the explanations, was the possibility that later opening times had succeeded in reducing binge-drinking.
They said that the new hours, which have been adopted by more than 60%, allowing them to open until midnight, 1am or beyond, might have reduced the incentive for young people to drive in search of a house party, or illegal drinking den, at the stroke of 11pm.
According to The Times, later closing times also mean that those drivers who do drink to excess are behind the wheel at times when there are fewer cars on the roads.
The authors acknowledge that the findings may appear counter-intuitive, but suggest that the change has cut the number of people killed or seriously injured on the roads by up to 500 a month.
The study covered the period 2002-08. Road-accident rates continued to fall after that, but official figures this month showed that alcohol-related road deaths last year may have risen for the first time in six years.